Influence of the COVID-19 Pandemic on Patients with Rectal Cancer.

: The COVID-19 pandemic and its associated restrictions have resulted in delayed diagnoses across various tumor entities, including rectal cancer. Our hypothesis was based on the expectation of a reduced number of primary operations due to higher tumor stages compared to the control group. : In a single-center retrospective study conducted from 1 March 2018 to 1 March 2022, we analyzed 120 patients with an initial diagnosis of rectal cancer. Among them, 65 patients were part of the control group (pre-COVID-19), while 55 patients were included in the study group (during the COVID-19 pandemic). We compared tumor stages, treatment methods, and complications, presenting data as absolute numbers or mean values. : Fewer primary tumor resections during the COVID-19 pandemic ( = 0.010), as well as a significantly lower overall number of tumor resections ( = 0.025) were seen compared to the control group. Twenty percent of patients in the COVID-19 group received their diagnosis during lockdown periods. These patients presented significantly higher tumor stages (T4b: 27.3% vs. 6.2%, = 0.025) compared to the control group prior to the pandemic. In addition, more patients with angiolymphatic invasion (ALI) were identified in the COVID-19 group following neoadjuvant treatment compared to the control group ( = 0.027). No differences were noted between the groups regarding complications, stoma placement, or conversion rates. : The COVID-19 pandemic, particularly during lockdown, appears to have contributed to delayed diagnoses, resulting in higher tumor stages and a decreased number of surgeries. The quality of rectal cancer treatment can be maintained under pandemic conditions.